On my 2000' ZX9R, which has a Muzzy Full Titanium Header on it, has been re-jetted with only the Main Jets increased in size. Stock being 160's on the outside carbs and 165 on the inside. I changed them to be 165 outside/170 inside. The bike is full of Power especially in the midrange and upper rpm's.

The question that I have is on the fuel/air mixture screws.

Kawasaki's Service Manual states that stock is set at 1 5/8 turns out on all (4), but the plugs are running white at that ratio. I turned them to 1 3/4 turns out, but they are still white.

I then cranked them to about 1 7/8 but still white.

I just turned them to about 1 15/16 and will have to check on it after a bit of riding. Last year when I set them to (2) complete turns out, I had flames coming out of the exhaust. That was with a k & N air filter, but I put that back to stock filter w/screen out.

I there another reason my plugs may be on the lighter side?

 

you need to check the plugs after you run it for a bit

 

Yup, it's a real fine line.... Mine is two turns, but at night on a no load rev, she'll shoot a little bit of flames also.. Put 4800 miles in the last 4 months that way, and no prob.. If I screw any less turns, she just doesn't run right. If I'm cranking on her driving, she won't shoot flames tho' ...

Also, if the plug is all ready burnt the ceramic.. you might try a new set of plugs, then redo your test a 1 15/16 ...??

 

Yes, I was driving it a week at a time before re-adjusting (about 200 miles total). They seemed a little better each time, but not good enough.

Took it for a ride today, first time since adjustment. It ran great as always and hopefully it's good this time. If not I'll try it at (2) turns out.

Thanks for the help! I'll let you know the results.

 

what do the instructions in your jet kit say. on my 7 its 2.5 turns out and you have to drill out a plug above the screw adjustment as well

 

I didn't have a jet kit for my bike. Stock jets for my bike is 160's outside/165 inside carbs. When I recieved this California model for some reason there were 150's across the board? Strange...

The bike had a K & N filter and a full Titanium exhaust. I figured bringing the mains up at 165 & 170 wouldn't be a bad choice? Or maybe 165 across the board would be better?

I also went back to the stock airbox.

The plug that you are speaking of, I think it's an air jet. Mine, being a Cal. model has an even smaller airjet than the 49 stater's. I have modified this bike to a non-Cal. model, except for this.

 

if you have a kn filter, full exhaust without a full jet kit, your going to run lean. eventhough you changed the main jets you still need to modify the pilot jets. spend the 100 bucks and get the kit and it will fix the problem.

 

I do understand that the pilot jets should also be replaced. but I also know it's not really easy to find Kehin Pilot jet's. I had a real hard time getting them for an earlier model Ninja a couple of years ago (but I was able to get them, for a price).

What I'm thinking is that the plugs I'm using are too cold? I'm not sure of the history of the bike, but the old plugs ran at a nice brown color last year even after re-jetting the main jets.

Does anyone know the difference between these (2) plug types.

When I bought the bike it came with CR9E plugs in it. The plugs also did not have the (2) electrodes on them, just (1).

Stock plugs are CR9EK with (2) electrodes on them. Are the CR9E plugs possibly a hotter plug?

I think I got the Hotter/Colder plug idea correct?

I also am running the Stock airbox with the screen removed, and not the K & N filter anymore. I had read that the K & N air filters actually make your bike run leaner. Not sure if that's correct, but that's just what I've seen on other forum's.

Thanks,

 

Try the NGK plugs, have always worked good for me.

Also like walight said, get a full jet kit and it will be better.
http://www.dynojet.com/pdf/2191.pdf

http://www.dynojet.com/jetkits/motorcycle/kawasaki.php

Call dynojet and they will ask you about rour bike, filter, exhaust and they will recomend the correct kit. There tech support is great too.

 

the only reason k/n filters cause a bike to run lean is b/c they allow more are into the air/fuel mixture, same with a high performance exhaust, thats why its recommended you rejet after modifiing anything with the air or fuel.